AS3 Make object visible/invisible depending on position of another object

I'm building a website with a gallery that slides from left to right using AS3 tweening, stopping at specific x coordinates to show a specific item.

When a coordinate is reached, I want to make information about the item visible.

I have this written and I don't understand why it isn't working. When I preview, the Info1 movieclip doesn't appear.

if (GalleryPanel.x==4715.45)
{
    Info1.visible=true;
}
else
{
    Info1.visible=false;
}

I'm a total noob.